Method of and means for charging barometric feed devices



R. M. SHERMAN 2,000,354

METHOD OF AND MEANS FOR CHARGING BAROMETRIC FEED DEVICES Filed April 20, 1952 May 7, 1935.

Patented May 7, 1935 UNITED. STATES METHOD OF AND MEANS FOR CHARGING BAROMETRIC FEED DEYICES Rallston M. Sherman, Glastonbury, Conn, assignor to The Silent Glowflil Burner Corporation, Hartford, Conn,

necticut a corporation of Con- I Application April 20,1932, Serial No. 606,509

12 Claims.

Thisinvention relates to barometric feed devices of the type commonly employing a liquidcontaining receptacle in which, despitewithdrawal of liquid therefrom, a constant level is in size,since during the normal use of the burner no occasion will arise for lifting or moving the reservoir from its established position. Since no substantial disturbance in the level of the liquid maintained by replenishment from a supply, tank fuel takes place during such replenishing process,

or reservoir in which a body of liquid is sustained by the maintenance therein of a sub-atmospheric pressure, the tank being so related to the receptacle through the maintenance of a communicating orifice, normally sealed by the liquid, that a supply of liquid in the receptacle is automatically replenished from the tank while preserving in the receptacle a substantially constant liquid level.

Barometric feed devices of this type are commonly used for the purpose of supplying liquid fuel to liquid fuel burners of the so-called combustion-tube type where liquid fuel is supplied by gravity from the constant level receptacle to the fuel grooves of the burner and there vaporized and burned with a suitable mixture of air. Such barometric feed devices usually comprise an inverted glass bottle, the open mouth of which is submerged or covered by the liquid fuel contained in an underlying constant level receptacle from which the liquid fuel is fed by gravity through a connecting feed pipe to the base :of the burner, the bottle being removable from its support so that it can be placed right side up, refilled and again replaced in its inverted posi-, tion, when it becomes necessary to refill it orreplenish its supply.

One of the objects of the present invention is the provision of means to replenish the supply of liquid in the tank or reservoir of a barometric feed device without the necessity of disturbing the positionof the tank, and at the same time without. disturbing to any substantial extent the level designed to be maintained in the constant level receptacle.

In case of a barometric feed device employed for combustion tube burners such as have been referred to, it is highly desirable that a substantially constant liquid level be maintained. If the level is unduly raised, the burner tends to become flooded, and if substantial variations in level 00- our while the burner is in operation, the action of the burner is seriously affected either by a raising or a lowering of the liquid level in the constant level receptacle. The present invention provides means for replenishing the tank or reservoirof such a burner without removing the tank or reservoir from its support, and such reservoir, if desired, may be permanently established in position andmay also be materially increased the tank may be refilled irrespective of whether the burner at the same time is in or out of operation and without disturbing or impairing the action of the burner during the replenishing process;

The invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the; appended claims.

In the drawing,--

Fig. l is an elevation, partially in section and partially diagrammatic, showing the principal operative parts comprising the illustrative embodiment-of the invention; 1

Fig. 2'is an enlarged detail in section showing one end of the pump With the check valves employed thereat; and s Fig. 3 shows a modified form of the pumping arrangement.

Referring to the drawing, there is shown for illustrative purposes a barometric feed device employed for the purpose of supplying liquid fuel to a combustion tube burner, such fuel being herein referred to as oil for the purpose of description. Such device comprises a constantlevel, bowl-shaped receptacle 5 having an enlarged upturned mouth formed by the sides 1 through which it is supported on the floor by the legs9 and within which mouth is supported the tank or reservoir 1 I. The latter may be of glass, metal, or any other'suitable material capable of maintaining a partial vacuum or sub-atmospheric pressure in the upper part of its interior, which for brevity (though somewhat inaccurately) may be referred to as the vacuum space.- The tank may be removable from its support or, if desired, permanently fixed in position. The bottom of the tank is herein provided with an open mouth I3 which projects downwardly into the'oil carrying part of the bowl where the oil at its normal level provides a liquid seal for the mouth. The

liquid in the bowl is subject to atmospheric pressure through the orifices l5l5.

Assuming the tank filled or partially filled, the oil supply in the bowl is maintained at a 0011-! stant-level by conditions well understood in the art. So long asthe mouth I3 is subject to the liquid seal, the body of oil in the tank I! is held contained piston 21 and piston rod 29.

sustained by the difference between the external atmospheric pressure and the sub-atmospheric pressure in the vacuum space. As oil is withdrawn from the bowl, tending to drop the level of the oil therein, the liquid seal is broken and air enters, passing to the upper part of the tank and permitting escape through the mouth into the bowl of a suflicient quantity of oil to maintain the level re-seal the mouth, and re-establish conditions of equilibrium.

The burner H, which typifies any of the usual forms of combustion tube burners, such, for example, as that disclosed in my prior Patent No. 1,676,223, has its base connected through the burner supply pipe IS with the bottom of the bowl 5, there being also provided the intervening controlling valve 2|. The operation of the burner depends in large measure on the proper alignment of the burner grooves with relation to the level of the oil in the tank 5, as is repre sented by the dotted line 23, and on themaintenance of the oil level to correspond to that line.

To replenish the supply of oil in the tank, while maintaining substantially the same liquid level in the receptacle, means are provided for adding tank, and concurrently withdrawing air from the upper part thereof to reduce the pressure therein. This operation may be carried out in various ways, but herein there is" provided a pump which may be either manually or power operated, the same comprising a cylinder 25 with One end of the pump cylinder communicates through the passage 3| and the inwardly opening check valve 33 (see Fig. 2) with an air suction pipe 35 which extends through a suitably packed orifice in the bottom' of the bowl, and up through the bowl into the tank I I, its open end being located near the top of the vacuum space therein. The same end of the pump cylinder also communicates through the passage 31 and the outwardly opening check valve 39 with an air discharge connection 4 I. a

The opposite end of the pump cylinder is connected through a passage and an outwardly opening check valve (similar to the check valve 39) with an oil delivery pipe 43 which extends through a suitably packed orifice in the bottom of the bowl to some point where it is capable of adding the oil discharged thereby to the liquid body either by delivering it into the bowl or into the space within the tank I I. Preferably, though not necessarily, the pipe 43 extends into the body of the tank for a sufiicient height so that the delivery of oil by the pump will not act to disturb by agitation the level of the oil in the constant level receptacle. piunp cylinder communicates through an inwardly opening check valve (similar to the check valve 33) with an oil suction pipe 45, which latter extends to approximately the bottom of an oil receptacle from which the main oil supply is derived, this being herein diagrammatically represented as a main oil tank which may be fixed or portable and located at any desired position with relation to the barometric feed device and to the pump.

When it is desired to replenish the supply of oil in the reservoir or tank II, the pump is actuated by reciprocating the piston 21. Movement of the piston in one direction serves to draw oil from the tank 41 into the oil end of the pump The same opposite side of the cylinder and at the same time to expel the air from the opposite or air end of the cylinder. The next succeeding movement of the piston in the opposite direction serves to withdraw a definite measured volume of air into the air end of the pump cylinder from the vacuum space of the tank I I, and simultaneously to replace it by the forcible introduction of a definite measured volume of oil expelled from the opposite or oil end of the pump cylinder. The refilling action is then continued by further reciprocations of the pump piston until the tank II is filled or the desired replenishment is eifected.

While a single pump cylinder is thus provided, through the valve arrangement in opposite ends of the cylinder, two positive displacement pumping means are actually embodied in this double acting pump, one for pumping oil and the other for pumping a definitely related volume of air,

and, if desired, these two pumping means might nected for concurrent operation.

The removal from the vacuum space (at the sub-atmospheric pressure then established therein) of a volume of air less than, or merelyequal to, the volume of oil concurrently introduced would cause some alteration of the oil level in the bowl, since, to support the added height of the liquid body without change in the level, a still lower sub-atmospheric pressure must be established. If, as would usually be the case, the quantity of oil in the bowl 5 is substantially less than that in the tank I I, the oillevel would be subject to a substantial rise if the volume of air withdrawn were no greater than that of the oil entered.

If, on the other hand, too great a volume of air is withdrawn, the mean level will not be altered for the oil body in the tank will tendfirst to rise, uncover the mouth and break the liquid seal, this being followed by the admission to the vacuum space of sufiicient air to correct for any excess withdrawn and then by the lowering of the oil body, the closing of the liquid seal and the re-establishment of equilibrium. Although, un-

derthese conditions, the mean level is kept the same, this action may be accompanied by some agitation of the oil in the bowl.

Accordingly, it is desirable to withdraw a volume of air somewhat greater than the volume of oil introduced, and preferably such an excess of air as will itself reduce the sub-atmospheric pressure to a point which will maintain the body of oil in the tank without any substantial tendency either to rise or descend with relation to the bowl. These conditions may be met by a variety of means. In the apparatus described, not only is the air withdrawn simultaneously with the introduction'of the oil, but the volume of airwithdrawn may be adjusted to exceed that of the oil introduced by exactly the required amount.

For this purpose, the air capacity of the pump exceeds the oil capacity by an amount sufllcient to yield the excess required for the liquid to be dealt with. This is due to the fact that the capacity of the oil end of the cylinder is reduced by the space occupied by the piston rod 29. The air suction pipe 35 is also slightly larger than the oil delivery pipe 43, there being provided, however, in the pipe 35, between the bowl and the pump, a reducing valve 5| by which, if desired, the amount of air withdrawn contemporaneously with the entering of each charge of oil may be cut down to the amount'which will not only prevent any rise of oil level in the bowl, but,if desired, may be such as to prevent any agitation of the oil in'the bowl due to too great a withdrawal of air. This provides means whereby the apparatus may be readjusted when required to deal withoils or other liquids of difie'rent specific gravities, the heavier the liquid the'greater the amount of air required to be withdrawn in order to maintain the equilibrium of levelconditions referred to. The oil and air pipes and 43 may, if desired, be provided beneath the bowl with shutoff valves (not shown). l In-Fig. 3 there is shown 'a modified arrangement of the pumping apparatus by which substantially the same results may be accomplished. There is here provided two rotary pumps, one an oil'pump 53 and another an air pump-55, mounted side by side to be driven by the same electric motor 51. Each pump is of the positive displacement type, such, for example, as the well-known eccentric vane construction, that is tosay, capable of discharging in each cycle of operation a definite measured volume of fluid, and of such relative capacities, either through inherent design or through the provision of suitable controlling devices, that in one cycle of operation the volume of air withdrawn by the air pump is slightly greater than the volume of oil discharged by the oil pump. The air pump has a discharge connection 4| similar to 4| in Fig. l, and is connected to an air suction pipe 35 which enters the tank in the same manner as the pipev 35. The oil pump has an oil suction pipe leading to the main oil tank 41, similar to the pipe 45, and an'oil dischargepipe 43' connected to the bowl or tank in the same manner as the pipe 43 in Fig. 1.

While the illustrative arrangement, such as is shown in Fig. 1, provides ideal conditions for the maintenance of the" level equilibrium as explained, it is not essential for such purpose that any given charge of liquid .be added to the main liquid body in exact coincidence with the withdrawal of a balancing volume of air,.so long as the aggregate volume-of liquid added and the aggregate volume of air withdrawn are'suchas to cause no substantialchange in the level of the liquid in the bowl either during or at the close of the process of replenishment.

Charges of liquid might be entered and. volumes of'air withdrawn in alternation in such small'amount as to cause no appreciable fluctuation in the liquid level during the process of replenishment and no appreciable change in the liquid level at the termination of such replenishment. For example, in the case of the rotary pumps disclosed in Fig. 3, these might be turned slowly by hand instead of through an electric or other motor, under which conditions the volume of liquid entered and the volumeof air withdrawn at each impulse would be so relatively small that no appreciable fluctuation in the liquid level would occur. Nor, so long as the two pump means are operated in timed relation and their volumetric capacities are properly related, is it necessary that the impulses of one should coincide exactly with the impulses of the other, but such impulses might be overlapping or in alternation.

On the other hand, charges of liquid might be entered and volumes of air withdrawn in alternation and of greater volume than those represented by each impulse of the eccentric vane pump but with such rapidity that the unbalancing action of an entered liquid charge would have no opportunity to act to upset the equilibrium before the balancing or corrective action of the air withdrawal takes place. f

Accordingly, in referring to the concurrent" or coinciden addition of the liquid and withdrawal of the air, or-concurrent' orcoincident operation of the pumps, I intend to include such timing of the liquid addition and air withdrawal as will provide for replenishment without substantial changes, either temporaryor final, in the level of the liquid in the bowl,

While I have herein shown and described for the purpose of illustration one specific application of the invention and the constructional details of one embodiment thereof, it is to be understood that extensive deviations may be made from the form, construction and relative arrangement of parts and that'various other applications of the principles. herein set forthmay be made, all without departing'from the spirit-of the invention. 1

l. The combination with a constant level bar.- ometric liquid feed device, which body of liquid is sustained by the maintenance of a sub-atmospheric pressure space, of replenishingmeans comprising a main liquid supply tank, aliquid pump, an intake connection between the pump and said supply tank,,a discharge connection from the liquid pump to said barometric feed device, an air pump having an intake connection opening into "said, sub-atmospheric pressure space, a discharge connection opening into the,

atmosphere, and means for operating said liquid and said ail-pumps simultaneously tosupply liquid to the device, and simultaneously ,with-, draw air therefrom in, such relative volumeand for such relative time as to insureagainst rise of the constant levelmaintained thereby.

/ 2. The combination with a constant level barometric liquid feed device, which body of liquid mospheric pressure space,'of replenishing means comprising pumping means for adding to said body a measured volumeof liquid, and pumping means for concurrently withdrawing from said space a greater volume of air at least sufiicient to compensate for the measured'volume ofliquid.

3. The combination with a constant level barometric liquid feed device, which body of liquid is sustained by the, maintenance of a sub-atmospheric pressure space, of replenishing means comprising a double acting pump having. connections communicating with the sub-atmospheric pressure space and having other connections communicating with said barometric feed device for pumping and adding liquid to said liquid body VII simultaneously with the said withdrawal of air from said space and in amount small enough to be compensated for by the withdrawn air.

4. The combination with a barometric liquid feed device comprising a feeding tank, the upper part of which is hermetically closed to permit the maintenance of asub-atmospheric pressure to sustain therein a body of liquid, of a constant level receptacle fed therefrom and communicating with the lower part of said tank through an orifice normally submerged in the liquid of said receptacle and providing a liquid seal thereat, means for replenishing said tank comprising an air eduction conduit communicating with the subatmospheric pressure space in said tank, a liquid discharge conduit extending into said tank above said liquid seal, and pumping means connected to said eduction conduit and said discharge conduit for concurrently withdrawing air from said 40 is sustained by the maintenance ofa sub-atspace and adding liquid to said liquid body in an amount compensated for by the withdrawal of air.

5. The combination with a barometric liquid feed device comprising a feeding tank, the. upper part of which is hermetically closed to permit the maintenance of asub-atmospheric pressure tosustain therein a body of liquid, of a constant level receptacle fed therefrom and. communicating with the lower part of saidtank through an orifice normally submerged in theliquid of said receptacle and providing a liquid seal thereat, means for replenishing said tank while maintaining substantially the same liquid level in the receptacle, the same comprising means to add a volume of liquid to. said liquid body, and means to concurrently withdraw from the subeatmospheric pressure space of said tank a volume of air which at the pressure there prevailing is greater than the said volume of liquid. I

6. The combination with a barometricdiquid feed device comprising a feeding tank, the upper part of which is hermetically closed to permit the maintenance of a sub-atmospheric pressure to sustain therein a body of liquid, of a constant level receptacle fed therefrom and communicating with the lower partof said tank through an orifice normally submerged in the liquid: of said receptacle and providing a liquid sealthereat, means for replenishing said tank while maintaining substantially the samev liquid level in the receptacle, the same comprising means to add a volume of liquid to said b0dy,-and means to withdraw a definitely proportioned volume of air from the sub-atmospheric pressure spacefof said tank concurrently with the addition f liquid to the body. w I

'7. The combination with a barometric liquid feed device comprising a feeding tankflthe upper part of which is hermetically closed to permit the maintenanceof asub-atmospheric pressure tosustain therein a body'of liquid, of a constant level receptacle fed therefrom and' communicating with the lower partof said tank through an orifice normally submerged in the liquid of said receptacle and providing a liquid seal thereat, means for replenishing said'tank comprising positive displacement pump means for withdrawing air from said sub-atmospheric pressure space, and positive displacement pumping means for concurrently adding liquid to said liquid body.

8. The combination'with a barometric liquid feed device comprising a feeding tank, the'upper part of which is hermetically closed to permit the maintenance of a sub-atmospheric pressure to sustain therein a body of liquid, of a constant level receptacle fed therefrom and communicating with the lower part of said tank through an orifice normally submerged in the liquid of said receptacle and providing a liquid seal thereat, means for replenishing said tank comprising positive-displacement, air-pumping means, positivedisplacement, liquid-pumping means, and means connecting said pumping means to operate the same to move their fluids concurrently.

9. The combination with a barometric liquid feed device comprising a feeding tank, the upper part of, which is hermetically closed to permit maintenance of a sub-atmospheric pressure to sustain therein a body of liquid, of a constant level receptacle fed therefrom and communicating with .the lower part of said tank through an orifice, normally submerged in the liquid of said receptacle and providing a liquid seal thereat, means for replenishing said tank while maintain.- ing substantially the same liquid level in the receptacle, the same comprising means to add liquid tothe said liquid body, and means concurrently to withdraw air from the upper part thereof to reduce the pressure therein.

10. The method ofreplenishing the liquid in a constant level barometric feed device, in which a body of liquid is sustained by the maintenance of a sub-atmospheric pressure space, which consists in adding to said body a volume of liquid and concurrently withdrawing a volume of air which, at the pressure prevailing in said space, is greater than the volume of liquid added.

7 11'. The method of replenishing the liquid in a constant level barometric feed device, in which a body-of liquid is sustained by the maintenance of a sub-atmospheric pressure space, which consists in adding to said bodya volume of liquid, concurrently withdrawing by eduction a volume of air definitely related to said volume of liquid, thus preserving substantially constant the level maintained by said device.

12. The method of replenishing the liquid in a constant level barometric feed device, in which a'bodyof liquid is sustained by the maintenance of asub-atmospheric pressure space, which consists in adding to said body a definitely measured volume of liquid, and concurrently withdrawing by: eduction a definitely measured volume of air.

' RALLSTON M. SHERMAN. 

